The present invention relates to a coupling component in which a tube element is expanded to press friction shoe assemblies against a second coupling component.
Known coupling assemblies, such as a brake or clutch, include a coupling component having an inflatable annular tube which is mounted on a rigid annular rim. A plurality of friction shoe assemblies are connected with the tube in an annular array. When fluid pressure is conducted to the tube, the tube is expanded to press the friction shoe assemblies against another coupling component to interconnect the two coupling components. Coupling components having this general construction and mode of operation are disclosed in U.S. Pat. Nos. 3,022,877; 3,092,231; 4,190,136; and 4,795,013.
Coupling components having this construction have previously been made by a method which includes placing the inflatable annular tube in a mold, inflating the tube, and heating the mold to vulcanize the elastomeric material of the tube. The tube is then removed from the mold and friction shoe assemblies are connected with the tube. Friction shoe assemblies have previously been connected with the tube by inserting pins through holes or passages formed in the tube during vulcanizing of the elastomeric material. The ends of the pins are received in openings formed in flanges on backing plates of the friction shoe assemblies. Releasable retainers, such as wires, are used to prevent the pins from becoming disengaged from the backing plates of the friction shoe assemblies.
When the friction shoe assemblies are connected with the tube by releasable pins or other types of torque transmitting elements, the friction shoe assemblies can be replaced when they become worn. However, a known coupling component has friction shoes which are bonded directly to the tube during the molding process. Thus, the inflatable tube is placed in the mold. The friction shoes are placed in an annular array in the mold with the friction shoes toward the tube. The tube is inflated and the mold heated to vulcanize the material of the tube and bond the tube with the friction shoes. Since the friction shoes are bonded with the tube, they cannot be replaced when they become worn.